An innovative prototype for better management of inhalational anesthesia, The Boston Anesthesia System, was developed by the Bioengineering Unit, Department of Anesthesia, of the Massachusetts General Hospital under the first three years of this project grant from the National Institute of General Medical Sciences. The System performs all the traditional functions required of an anesthesia machine but includes many innovative safety, display, and system monitoring functions. In the proposed renewal period, we will use this prototype as a foundation for developing a complete, integrated anesthesia management system including semi-automated record-keeping, comprehensive physiological monitoring, measurement of anesthetic concentration in the breathing circuit, and capablities of performing as a sophisticated anesthesia training simulator. This advanced anesthesia research instrumentation will employ a sophisticated communication structure that preserves the inherent safety and reliability of the anesthesia administration functions while allowing flexibility and innovation of application. The BAS will act as a separate device within the instrumentation system and will contain a fixed, unalterable operating program separate from and unaffected by recording, monitoring, or display activities. The instrumentaton system will be used to test the feasibility and value of various strategies for semi-automated record-keeping. Programs (software) will be developed for simulating important anesthesia crises and developing understanding of anesthetic uptake and distribution. A simple, rugged, inexpensive anesthetic gas sensor will be developed and, if results warrant, integrated within the instrumentation system for laboratory and animal trials and for use in the record-keeping and simulation activities. The record-keeping will also provide critical and unique documentation of machine performance and patient response during clinical trials of the BAS. As in the first three years, we will continue to propgate the concept of a systems approach to the design of anesthesia apparatus and will work towards the safe and effective transfer of the technology developed.